BUG #15451: Error adding foriegn key constraint

The following bug has been logged on the website:

Bug reference:      15451
Logged by:          Harry Clarke
Email address:      harry@harryclarke.me.uk
PostgreSQL version: 10.5
Operating system:   Windows Server 2008 R2 standard
Description:

When trying to create a table, or to add a foreign key constraint to a
table, an error (see below) is produced. However, both tables are permanent
tables, and there are no temporary tables that I am aware of.

ERROR: constraints on permanent tables may reference only permanent tables

ALTER TABLE bnm.table1
    ADD CONSTRAINT id_fk FOREIGN KEY (bnm_id)
    REFERENCES bnm.table2 (id) MATCH SIMPLE
    ON UPDATE NO ACTION
    ON DELETE NO ACTION;